 He returned to Russia afterwards, and became chef of the Neva Musketeer Regiment on 7 February 1800, while serving as the governor of Vryborg as well as the chef of the Vryborg Garrison regiment between March and August in 1800.He then served in the next war against Napoleon in Poland in 1806–1807 (Battle of Heilsberg).He succeeded Barclay de Tolly as the Minister of War in August 1812, and was promoted to general of the infantry on 11 September 1814.